ML20199L445

Forwards for Review & Comment Revised Draft Info Notice Re Inservice Testing of A-4 Multimatic Deluge Valve for Farley NPP Units 1 & 2.Informs That Comments Submitted on 981120 Were Reviewed & Incorporated Where Appropriate

ML20199L445
Person / Time
Site:	Farley
Issue date:	01/25/1999
From:	Berkow H NRC (Affiliation Not Assigned)
To:	Dennis Morey SOUTHERN NUCLEAR OPERATING CO.
References
NUDOCS 9901270234
Download: ML20199L445 (8)

Text

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January 25, 1999 Mr. D. N. Morey Vice President - Farley Project Southern Nuclear Operating Company, Inc. I Post Office Box 1295 Birmingham, Alabama 35201-1295 I

SUBJECT:

REQUEST FOR A TECHNICAL REVIEW OF REVISED DRAFT INFORMATION NOTICE REGARDING INSERVICE TESTING OF THE A-4 MULTIMATIC DELUGE VALVE - JOSEPH M. FARLEY NUCLEAR PLANT, UNITS 1 AND 2

Dear Mr. Morey:

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The U.S. Nuclear Regulatory Commission is planning to issue an information notice (IN) discussing the failure of several preaction sprinkler system deluge valves at Joseph M. Farley  ;

Nuclear Plant, Units 1 and 2. By letier dated November 13,1998, we requested your review of Revision 0 of the draft information notice. You responded, with comments, by letter dated November 20,1998. We have reviewed your comments and incorporated them where appropriate. We request that you review the enclosed revised draft IN to ensure the technical j information regarding the event is accurate. Your cooperation in this matter is appreciated. '

l The enclosed IN has been discussed with Mark Ajtuni of your staff. A target date for your written comments has been agreed upon to be Goruary 12,1999. Should a situation occur that prevents you from meeting the target date, please contact Jacob l. Zimmerman at (301) 415-2426. l Sincerely, i Original signed by:

Herbert N. Berkow, Director i Project Directorate ll-2 Division of Reactor Projects - 1/Il Office of Nuclear Reactor Regulation Docket Nos. 50-348 and 50-364

Enclosure:

As stated cc w/ encl: See next page plSTRIBUTION: i Docket File JZwolinski Pskinnw, Rll MSalley PUBLIC PBerkow TJohnson,Ril JRoe PDil-2 RF L8erry GHolahan RDennig ACRS JZimmerman TMarsh WBurton '

OGC LRPlisco, Ril SWest DOCUMENT NAME: G:\FARLEY\lNREV1.WPD OFFICE PDil-M PDil-2/LA PECB/C /

YLB/C ,T PDil-?/D, NAME J. MAN:en L. BERRY R.DENNIG T. MARSH f H[BE W DATE /b /99 l / N /99 / / E/ /99 \ / N /99 [1 ' /99 COPY ES NO YES[Nh YES NO YE h NO YESNbl OFFICIKL RECORD COPY 9901270234 990125 ;er "'

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2 j NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 2006H001  !

.....# January 25, 1999 1

Mr. D. N. Morey l

Vice President - Farley Project 1 Southern Nuclear Operating Company, Inc. l Post Office Box 1295 Birmingham, Alabama 35201-1295 l

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SUBJECT:

REQUEST FOR A TECHNICAL REV!EW OF REVISED DRAFT INFORMATION i NOTICE REGARDING INSERVICE TESTING OF THE A-4 MULTIMATIC DELUGE VALVE - JOSEPH M. FARLEY NUCLEAR PLANT, UNITS 1 AND 2 l

Dear Mr. Morey:

l The U.S. Nuclear Regulatory Commission is planning to issue an information notice (IN) discussing the failure of several preaction sprinkler system deluge valves at Joseph M. Farley Nuclear Plant, Units 1 and 2. By letter dated November 13,1998, we requested your review of Revision 0 of the draft information notice. You responded, with comments, by letter dated November 20,1998. We have reviewed your comments and incorporated them where appropriate. We request that you review the enclosed revised draft IN to ensure the technical information regarding the event is accurate. Your cooperation in this matter is appreciated.

The enclossd IN has been discussed with Mark Ajiuni of your staff. A target date for your written comrnents has been agreed upon to be February 12,1999. Should a situation occur that prevents you from meeting the target date, please contact Jacob l. Zimmerman at (301) 415-2426.

Sincerely, Y l1' -

Iprbert N. Berkow, Director

/ Project Directorate ll-2 Division of Reactor Projects - 1/11 Office of Nuclear Reactor Regulation Docket Nos. 50-348 and 50-364

Enclosure:

As stated cc w/ encl: See next page

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Joseph M. Farley Nuclear Plant cc:

Mr. L. M. Stinson Rebecca V. Badham General Manager- SAER Supervisor Southern Nuclear Operating Company Southern Nuclear Operating Company l Post Office Box 470 P. O. Box 470 Ashford, Alabama 36312 {

Ashford, Alabama 36312 i Mr. Mark Ajiuni, Licensing Manager Southern Nuc! ear Operating Company Post Office Box 1295 Birmingham, Alabama 35201-1295 l Mr. M. Stanford Blanton Balch and Bingham Law Firm Post Office Box 306 1710 Sixth Avenue North Birmingham, Alabama 35201 Mr. J. D. Woodard Executive Vice President Southern Nuclear Operating Company Post Office Box 1295 Birmingham, Alabama 35201 State Health Officer Alabama Department of Public Health 434 Monroe Street '

Montgomery, Alabama 36130-1701 Chairman Houston County Commission Post Office Box 6406 Dothan, Alabama 36302 Regional Administrator, Region 11 U.S. Nuclear Regulatory Commission Atlanta Federal Center 61 Forsyth Street, S.W., Suite 23T85 Atlanic, Georgia 30303 -

Resident inspector U.S. Nuclear Regulatory Commission 7388 N. State Highway 95 Columbia, Alabama 36319 l

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! UNITED STATES NUCLEAR REGULATORY COMMISSION i

OFFICE OF NUCLEAR REACTOR REGULATION WASHINGTON, D.C. 20555-0001 February xx,1999 NRC INFORMATION NOTICE 99-XX: FAILED FIRE PROTECTION DELUGE If.VES AND i

POTENTIAL TESTING DEFICIENCIES IN PREACTION SPRINKLER SYSTEMS /' W

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y hr l Addressees # '\ f J][ y . My All NRC licensees. N/ h vJf l Purcose 4 A'

(NRC) is iss}ing this informatiol The U.S. Nuclear Regulatory Commission u addressees to test methodologies for fire protection deluge valves that may not adequately demonstrate valve operability. It is expected that recipients will revie,w the information for applicability to their facilities and consider actions;as appropriate, to avoid similar problems.

However, suggestions contained in this information notice are not NRC requirements; therefore, no specific action or written response isiequired8 ~

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Valves for sprinkler system automatic control (SSAC) are used in fire protection systems that protect are,as housing safety-related equipment and that also protect non-safety-related

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equipment used for safe' shutdown. Many,of these systems are used to provide primary fire

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protection and to meet the, requirements of"10 CFR Part 50, Appendix R, Section Ill.G. Poor design, deficient maintenance, or' inadequate testirig of SSAC valves and associated solenoid valves can leed to a common 2 mode failure of the valves to perform their design function of providing adeqDate and reliable fire protection. This, in tum, can result in the failure of safety-related equipment and the inability to achieve and maintain a safe reactor shutdown condition if a fire occurs.  ;

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! TheWodel A-4 Multima ic Valve manufactured by Grinnell is a deluge valve designed for use in fiJe protection systems! It is' used as a system control valve in deluge, preaction, and special

}ypes of fire protection' systems and may also provide for actuation of fire alarms when the systerns operate. ,f 1 ,. 'n Gr i

Plea'ctio'rivalves contain connections for monitoring pressure in the diaphragm chamber and in the main water supply, for providing valve drainage and for supplying water to the diaphragm chamber.' All required components for these connections are typically supplied by the valve manufacturer as " trim packages" and are included as part of the Underwriters Laboratories (UL) and Factory Mutual, Inc. (FM) certifications of the valves.

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IN 99-xx February xx,1999 Page 2 of 5 Descriotion of Circumstances l

In the week of March 4,1996, during surveillance testing of preaction sprinkler systems in the Farley Unit 1 fire protection system,5 of 11 SSAC valves (Grinnell Model A4 deluge valves) failed to trip open when water pressure was vented out of the diaphragm chamber. Upon additional testing, the licensee found that several other SSAC valves failed. The/ cot-cause team, formed after the initial valve failures, concluded that the diaphragm was sticking to its retainer and push rod disk, that the push rod assembly showed wear (pits and eroded plating),

and that the associated solenoid valves were not properly ble.eding w,ater pregsure out of the diaphragm area.

j4/ R using an abrasive cle'a h

The investigators found that the licensee was chrome-plated push rod and the push rod guide in the'diaphragrd retainers.'The teamV theorized that this activity may have created rust particles that caused the sticking. In like manner, abrasives used to clean the solenoid valves c'ould cause the plunger assembly to stick.

Grinnell does not recommend using any abrasives that [emove metal because the solvents attack the valve seats and the main orifice. Grinnell recom' mends cleaning the push rods, guides, and solenoid valves with only soap, water, and clean cloths. n g y )

The root-cause team also found that the solendid valves were designed for operating pressures of approximately 150 psig (UL maximum rated pressure is 175 psig),?whereas the actual operating pressures often exceeded 150 psig (pressures sometim'es went as high as 225 psig).

The staff theorizes that the valves may not be able to ope'l aginst this pressure.

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Although the team did not conclusfvely detentiine the root cause of the valve failures, it l

recommended (1) replacing the. diaphragms'and solendid valves, (2) installing new solenoid valves with a design pressure of 200 psi (and factory tested to 300 psi), (3) flushing the solenoid valve piping and diaphragm chamber when cleaning the solenoids, (4) requiring the use of onfy soap, water /and a clean cloth when cleaning the solenoid valves, (5) cleaning the solenoid and SSAC valv'et more frequently, and (6) testing the valves more often - every 12 months instead of 18 months (in the short term, the licensee increased testing to every 2, 6, and 12 months after resetting'the valves to improve reliability).

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In subseque'nt walkdowns, the team found that the piping for the deluge valve control drain lines l had a 3/8-inch diameterinstead of the %-inch diameter line usually supplied as part of the trim packahe provided by t$e manufacturer and listed by the independent testing laboratory (i.e., UL

, or FM). The use of thelsrnaller drain line could potentially inhibit the bleedoff of water from the

! diaphragm chamber, resulting in increased pressure in the chamber. The staff notes that this I

restriction, in turn, could prevent the clapper from opening.

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i in mid-February '1998, the licensee performed a scheduled surveillance test on several deiuge l Valvec in the preaction sprinkler system. One valve failed to trip, and the push rod had to be f'orced back manually after completely isolating and draining the diaphragm chamber, closing the main isolation valve, opening the main drain, and opening the valve faceplate. Inspection of the rubber diaphragm showed a " dimple" near the diaphragm chamber supply inlet. The valve had been left in the tripped condition for about 22 days in May 1997, then it was reset and left in this position until this surveillance (for about 9 months). As a result of this failure, the licensee tested a sample of six additional valves that had been left in a tripped condition for long periods.

IN 99-xx February xx,1999 Page 3 of 5 One of these valves failed to trip electrically. Inspection of this valve indicated that the push rod appeared to be misaligned in the retainer ring slot and some corrosion had formed where the rod slides through the ring. Also, the diaphragm was stuck to the face of the push rod. In total, five of the six sample valves and one other valve failed to trip properly.

In June 1998, as part of the ongoing testing program, one of the deluge valves was manually actuated from its pull station; it failed to operate. An investigation indicated that'the pull station housing had rotated and was preventing complete travel (i.e., fully opeh) of,the valve handle.

After adjusting the pull station housing, the handle was actuated cya,n and th,e deluge valve successfully tripped. j ,

,f Q. 3' h The team commissioned by the licensee to study the problems with. e A-4 valves ~ concluded f

that, although the cause and effect are not known, it appears that the failure \ccurred within a tripped open valve exposed to pressure over time. Tss expos 6te caused the Oatve to fail when reset. The team noted that the manuf acturer does not recommend leaving the tripp'ed-open valves pressurized for a significant length of time. g. -ms y y >g The staff is continuing to monitor the licensee's investigation into the valve failures.

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Discussion #

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f} 'x% j;v The staff noted several potential problenis as a result of this dvent/First, as discussed above, when deluge valves were left in the tripped condition for'long periods, the potential arose for the rubber diaphragm to bond to the push rod and the flange diaphragm could remain partially, bondedstricting to theflow flange, from there/ When the diaphragm valves ar chamber, and keeping the valve from operating. Bonding may be particularly pronounced in systems using well water og. rap river wate'r. It is a co'mmon practice for many plants to keep their preaction sprinkler system deluge valves in~a tripped condition for long periods, usually during outage's when welding'or other activsies are taking place, which increases the likelihood of spurious system actu'ation. Grinnell recornmends that the valve be reset within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of any valve operation and that the intemal components of valves be cleaned and inspected after any valve op'eration.

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s t, Second, the'use of plant-supplied or plant-designed trim packages instead of the UL- or FM-certified packages an'd designs supplied by the valve manufacturer may result in issues such as undersized drain lines,hhich may restrict the bleedoff from the diaphragm chamber and further inhibit valve actuation. 4 V

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Jhird, an evaluation by Grinnell concluded that the valve release mechanism may be jamming from the high pressure and surging conditions in the deluge system. The jamming may be

@ elated to deep indentations on the valve latch. Cleaning and inspection of the valves' internal bomponents should reveal these potential problems.

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While reviewing this event, the staff noted that the licensee performs full-flow testing. It is the staff's understanding that many plants isolate the deluge valves from the main water supply during valve testing. This practice is a potential testing weakness and may mask the actuation problems discussed herein. With the deluge valve isolated, a limited volume of water is trapped in both the main line and the diaphragm chamber supply line. The water in the diaphragm

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IN 99-xx February xx,1999 Page 4 of 5 chamber is slowly bled off until the clapper opens. If the diaphragm has bonded to the flange, the inlet to the diaphragm chamber could be partially blocked, inhibiting (but not preventing) valve actuation. However, during normal operation with full flow from the diaphragm chamber supply line, the primary flow path would fc! low the supply line to the drain, thus trapping water in the diaphragm chamber and preventing valve actuation. Note the following statement in i National Fire Protection Association Standard 25 (" Standard for the Inspection, T,asting, and Maintenance of Water Based Fire Protection Systems," 1995 edition, section 94.3.2.2): "Each deluge or preaction va!ve shall be trip tested annually at full flow (en)ph' asis added] in warm weather and in accordance with the manufacturer's instructions." Ti}e valve manufacturer may also have special requirements for inservice testing. The'A-4 valve manufacturer recommends.

partial flow testing where ful!-flow testing is undesirableF /J rs %

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Another event involving the failure of automatic deluge valves took place at Grand Guffin1983, and is discussed in Information Notice (IN) 84-16, "Fallure'of A'utomatic Sorinkier, System l Valves to Operate." While the licensee was performind an operational test of the emergency '

diesel generator (EDG), a fire occurred in the diesel. The automatic deluge valve (6-inch Model C valve manufactured by the Automatic Sprinkidr C5mpany of America (ASCO)) failed to open. Approximately 3 months later, a Model C valvfin a preaction sprinkler system for the EDG room at Grand Gulf failed to operate during a'tdst. In both cases, scoring was found in the actuation weight upper guide collar and in the tiox that encloses th'e weight guide bushing.

g3 g jj v Another instance of repeated failures of a preactio,n deluge valve ~ occurred in 1997 at Limerick Unit 1. A Model"D" 6-inch deluge valve manufactured by. Star Sprinkler, Inc., did not actuate during a surveillance test. The frequency of testing had tieenincreased because of earlier failures caused by suspected mechanical problems. Continued troubleshooting of the valve failures uncovered a potential voltage mismatch betwedn the deluge valve and the Chemetron release control panel, resulting In marginal power available to operate the valve. The Model"D" valves g( were^ subsequently p' laced with rep y(odel

%9 "G" valves, siso manufactured by Star Sp Related Generic Communications %

e N 4  %,A Information Notice (IN)'8916,~ " Failure of Automatic Sprinkler System Valves to Operate," issued March 2, 984.

O f 2 dequ eYire Suppression System Testing," issued April 8,1992.

f y. f e / IN 97-22,"Potentiaifor' Failure of the OMEGA Series Sprinkler Heads," issued 3/ September 22,i997.

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f-IN 99-xx February xx,1999 Page 5 of 5 This information notice requires no specific action or written response. However, addressees are reminded that they are required to consider industry-wide operating experience (including NRC information notices) where practical, when setting goals and performing periodic evaluations under 10 CFR 50.65, " Requirement for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants." If you have any questions about the information in this l notice, please contact one of the technical contacts listed below or the appropriate Office of I Nuclear Reactor Regulation (NRR) project manager.

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l David B. MattNews, Directok.hMk Division . Reactor P gram Management [ i Office of Uiclear ctor Regul ' d.y.

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Technical contacts:

Rhh / ]$s Mark h. Salley, NRR R f Caldwell, Ril 301-415-2840 334-899-3386s E-mail: mxs3@nrc. gov (Mail:'rkc1On}c. gov

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William F. Burton, NRR (W+ q WQ 43%

301-415-2853 M ~V l

E-mail: wfb@nrc.g$foyfs

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Attachment:

List of Recently issued NRC Information Noticesp 4(, i

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